Young's Modulus of Simply Supported Beam: Is it True?

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The discussion centers on the formula for Young's modulus of a simply supported beam, expressed as E = (11/768)*(WL^3)/(I*Y), raising questions about the validity of the coefficient 11/768. Participants express uncertainty about its origin, suspecting it may relate to unit conversions. The conversation highlights the need for clarity regarding the type and location of the load, as well as the definition of Y, specifically whether it represents maximum deflection. Additionally, there is skepticism about the rearrangement of the equation to solve for E, prompting inquiries about the context of its use, such as experimental applications. Overall, the formula's accuracy and the assumptions behind it require further exploration.
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The young's modulus of a simply supported beam is given as E= (11/768)*(WL^3)/(I*Y)...
where W=Weight of the load
L=Length of the beam
I=Moment of inertia
Y=Deflection

Is this true?
 
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You need to explain the 11/768. I have a suspicion it is for unit conversions. It would be helpful if you explained. You also mention nothing of the force location or type, i.e. concentrated or distributed. There are a lot of beam equations out there for the scenario you describe.
 
Well, it could be. I got to admit 11/768 is a little strange looking. But, this could be something near 5/386. So, 3 questions?
Is y the MAXIMUM deflection?
Where are you measuring y?
Where is the load?
I don't think I've ever seen the equation re-arranged like this in order to determine E. Are you doing an experiment?
 
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